Eleven workers were taken to hospital after being exposed to a chemical leak at a wafer fabrication plant in Kallang Way yesterday afternoon.
The Straits Times understands that the leaked gas was nitrogen trifluoride - a colourless, odourless and non-flammable gas used in the plasma etching of silicon wafers.
The affected workers, who were taken to Tan Tock Seng Hospital, suffered from minor skin irritation, labour MP Melvin Yong said in a Facebook post last night. He expressed relief the workers had been "given the green light to be discharged".
All the affected workers were from RF360 Singapore - a joint venture between American telecommunications equipment company Qualcomm and electronics company TDK, which is based in Japan.
Mr Yong, who is tripartism director at the National Trades Union Congress, said that RF360 is a unionised firm under the United Workers of Electronics and Electrical Industries.
"The union is in touch with the company to provide the necessary assistance to the affected workers," said Mr Yong, adding that the union will also "follow up closely" with the firm to investigate the incident.
The production floor where the leak occurred has been blocked off for investigations, but staff were allowed to go back to work in other parts of the company around 7pm, ST understands.
A staff member, who declined to be identified, said he and other colleagues evacuated the building after hearing an announcement around 12.30pm about a gas leak.
The leak was shut off by an in-built safety system before officers from the Singapore Civil Defence Force (SCDF), which was alerted at around 1.40pm, arrived.
SCDF, which sent Hazardous Materials (HazMat) officers to the site, declared around 3pm that the incident was "contained within a sealed production room on the premises".
At about 3.50pm, the SCDF said its HazMat detectors showed no reading of the chemical vapour in the production room. "The surrounding environment is also safe, with no traces of the chemical in the air," it added.
When ST was at the scene around 3.30pm, a young woman was seen being escorted to an ambulance. While she looked shaken, she was able to make her own way to it.
A 38-year-old engineer, who declined to be identified, said the leak occurred on the third floor of the building. "I work on the second floor, and it happened in the clean room of a production area," he said.
In an announcement when the alarm sounded, workers were told to be on "standby" until investigations were completed, he said. After the environment was declared safe, workers were told to stay within company premises.
While they were not allowed to re-enter their workplace, they remained in the canteen to wait for further instructions, he added.
RF360 Singapore did not reply to media queries by press time.
In September last year, seven people were taken to hospital after a chlorine gas leak from an indoor storage facility at 3, Jalan Samulun.
SCDF officers at work at site of chemical leak. str.sg/4DZr